This invention relates to an improvement of the case for a timepiece.
A conventional timepiece is illustrated in FIG. 1 in which a case body comprises a case back cover 1, a case body 2, and a casing ring 3 which is secured to the case back cover 1. A timepiece movement 6 which operates dial hands is held within said case by the engagement of a projection 4 of the casing ring 3 with the recess 5 of said case body. This casing ring limits the lateral displacement of the movement 6 by its top wall 3a and regulates the axial displacement by holding a flange thereof between its upper surface 3b and the upper protruding portion 2a of the case body 2 through mediation of the dial plate 7. If an electric cell is used as a power source of the movement 6, said electric cell must be exchanged after its available operating period is exceeded.
The exchanging operation is accomplished by taking off the case back 1, but when the projection 4 of the casing ring 3 is out of the recess 5 of the case body 2, the top wall 3a of the casing ring damages the side wall 6a of the timepiece movement 6 and in turn there is a danger that the casing ring will be bent therefrom. Also the casing ring is such an essential element for holding the movement that it must be reshaped in case of re-assembling of the timepieces.